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From: Suleiman Souhlal <ssouhlal@FreeBSD.org>
Date: Sun, 29 May 2005 22:47:03 -0400
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Subject: [PATCH] randomized mmap
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Hi!

The patch at http://people.freebsd.org/~ssouhlal/testing/ 
mmap_random-20050528.diff implements random mmap addresses (unless of  
course MAP_FIXED is being used), again from OpenBSD.
This behavior can be disabled setting the vm.mmap_random sysctl to 0.
I think this could greatly increase memory fragmentation, so I'm not  
sure it would be such a good idea to have it on by default. Also, it  
doesn't really make attacks unfeasable, but the implementation is so  
simple that I don't think we really lose anything by letting users  
decide if they want to enable it or not.

Any comment?
--
Suleiman Souhlal     | ssouhlal@vt.edu
The FreeBSD Project  | ssouhlal@FreeBSD.org